Malicious PDF — malware analysis report

Static analysis result for SHA-256 39871c4508a42ea6…

MALICIOUS

PDF

79.9 KB Created: 2021-07-14 01:26:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: e12a2b1cba2986961ffa94e66fcdb4ce SHA-1: 9f4e4cfd0c8635e13c1ba37cf74a62d50b810777 SHA-256: 39871c4508a42ea632fe4a66d7d7e44a4a2841b57a4af667686a95d2ca5045b8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a malicious PDF, as indicated by ML classification and ClamAV detection. It contains numerous external links, many pointing to compromised WordPress sites, suggesting a link farm or phishing lure. The PDF is likely intended to redirect users to malicious websites for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://crewmak.ru/uplcv?utm_term=demonstrating+to+win+pdf PDF link annotation
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e231641b16---50415912766.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b9ba106fcbe---51549891783.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/u087f23g4tl20l1qrtf55k16q1/29953906642.pdfIn PDF document text
    • https://tootooair.com/FileData/ckfinder/files/20210618_445465091679C707.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/32147683495.pdfIn PDF document text
    • http://caramelitos.sk/files/19858547050.pdfIn PDF document text
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/7cb990235d33d2de26b8ac060885f593/93672832057.pdfIn PDF document text
    • https://ivanda-commerce.hr/userfiles/file/32311858505.pdfIn PDF document text
    • https://kham.vn/userfiles/file/xuzuragedanubazalovagono.pdfIn PDF document text
    • http://pensionpoint.cz/userfiles/files/58974841260.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16093f5eb4872c---17974702854.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607df3d25b1d7---dewuzexelugujabi.pdfIn PDF document text
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/c67b117eeb37f6e5c918541b31991ed9/balipokokebuza.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/pprfuvjs83ucke3kdkc6o1jc55/13372441698.pdfIn PDF document text
    • http://itkaufmann.com/images/fckimages/file/nudide.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16072f2e9e55cf---pikexeduveran.pdfIn PDF document text
    • https://oglethorpeclub.org/~oglethor/UserFiles/file/weloberuxuwurinalikab.pdfIn PDF document text
    • http://jpmoto.biz/upload_picture/porolibodemonanebogad.pdfIn PDF document text
    • http://poltinka.ru/userfiles/file/41625973026.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1606c659d6d93e---41151980568.pdfIn PDF document text
    • https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d43e5bd4f7---18962849411.pdfIn PDF document text
    • http://sanarina.de/ckfinder/userfiles/files/tivikavexumole.pdfIn PDF document text
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1606f18583fc34---81719581343.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c5cd888a399---53365838863.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e5a14d59044---94533375789.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/vvmdv6joosf4ldest6s34aqj5t/xonijalodek.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/ql75rra48fv1ko9sbrb361rd35/19390608516.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/ba3f6a0d4009a8d99dcd9a88d3899789/fajojuto.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d55c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD55C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED73 10880 bytes
SHA-256: 0593c069d00c5c3efb4a4d6b420a4cd486a06c9688860b6321373eaedd2b1bdd
font_02_sfnt_off00010673.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10673 16748 bytes
SHA-256: 3b890199d6ae663c296196a2353785027b342a31ec79a6e03ad7b1d93aa5dd6d